Demolition plans - model or annotate?

[HVAC-Novice]

For demolition plans i normally model in the "existing" phase the items to be removed adn the "demo" them in the new construction phase. and where the demo-elements interact with he model (i.e. a door in a wall.... and the hole int he wall gets then filled it) that is probably the best method. 

But for items that are not really connected to the model (ductwork, mechanical equipment) i now go the idea to just annotate with dashed lines. In most cases we only use a floorplan with key notes. We also don't schedule demo equipment. this would have the advantage of not having to deal with view depths and properly connected pipes and duct fittings etc. So I can't really see a disadvantage of simplifying this.

For new construction I pay attention to actually model everything the way it is supposed to be and not to hack something. but demo items only need to look like demo items to give the contractor an idea what to demo. 

Will I regret oversimplifying this or is there a good reason to model all demo elements? 

[Redrunner92]

If you are and will be the only person working on the Revit project, go ahead and detail the non-built-in items to your content.

If anyone else is working on or will work on the Revit project, I suggest you model the demolished items rather than use detail lines and detail items. This has the advantage of clarity: another person/other people working on the model will be able to simply select an item and its identity will be clear in the Properties palette (assuming all items are made clearly and correctly). In contrast: with detail items, especially dashed lines, an object's identity is often not so clear. The identity may lie in a note block or key note somewhere (and on that note, Keynotes will not select detail lines as their hosts), which could take another person some time to find.

I work in an architectural company and as such do make much use of Revit's MEP items. Instead, one thing I do commonly is create my own custom families which are the shape and size of MEP items, but have none of their MEP-specific properties. Usually they have size parameters and one or more material parameters, that's it. This makes them: quick to create; actual modeled elements which I can demolish; able to host Keynotes; and it avoids the errors Revit generates when MEP items don't connect correctly, don't make a complete circuit, etc. (I expect the consultants to notify me of such errors and to create solutions for them, so I don't need Revit's errors which would merely bog down my model.)

This simple-custom-family approach for MEP items might not work well when working with consultants whom also use Revit and therefore create their own linked files, but so far none of the consultants I work with use Revit--they use AutoCAD--so I can get away with it. Though I will certainly be eager to work with a consultant who uses Revit if I ever get the opportunity.

There are a couple thoughts, take them or leave them.

[barthbradley · Accepted solution]

Are you saying your "Existing" phase ONLY contains elements that are demolished in "New Construction" Phase - and, if those "Existing" Elements require a host, such as a Door requires a Wall, you model INFILL hosts that are also demolished in "New Construction"??? 

[HVAC-Novice · Accepted solution]

Thanks for the reply. I knew the answer "depends". I forgot to mention, I would be the only one working on the plans. 

Yes, for mechanical equipment I just created a dumb mechanical family that is a cuboid and I can use it as a n AHU, boiler or whatever I need to demo. For built-in equipment (i.e. louver in a wall), I just use that family. 

maybe I just continue with that practice. 

[barthbradley]

I'm still curious if I read you right.  

[Redrunner92 · Accepted solution]

I advise you do continue using that method, if for nothing else that none of us knows what the future holds. Modeled items are more easily relied upon than detail items for unforeseen changes, simplifying changes in views (I have needed to create multiple views of an Existing phase before which, til that moment, I thought would only show up in one view: the demolition plan), and quick identification of objects. But I will grant that detail items can often be faster to initially place, so for one-and-done demolition view situations with only one person using the Revit file, using mostly detail items would work just fine.